CN104745113B

CN104745113B - Self-adhesive article with foam carrier

Info

Publication number: CN104745113B
Application number: CN201410838590.5A
Authority: CN
Inventors: D.古巴尔; O.拉费特; H.特罗亚德克
Original assignee: Bostik SA
Current assignee: Bostik SA
Priority date: 2013-12-30
Filing date: 2014-12-30
Publication date: 2020-05-15
Anticipated expiration: 2034-12-30
Also published as: JP2015129280A; EP2889348B1; US20150184043A1; ES2713433T3; FR3015984B1; EP2889348A1; US20170058166A1; FR3015984A1; US9493690B2; US9976066B2; CN110205045A; CN110205045B; JP6552819B2; CN104745113A

Abstract

The invention relates to a self-adhesive article comprising a support layer of foam or similar type and an adhesive layer obtained by cross-linking the adhesive composition. The invention also relates to a mixture of at least two polymers suitable for producing the self-adhesive article and to an adhesive composition comprising the mixture of at least two polymers according to the invention.

Description

Self-adhesive article with foam carrier

Technical Field

Background

Pressure-sensitive adhesives (also known as self-adhesives or psa (pressure sensitive adhesive)) are substances which give the support layer (also known as substrate) coated therewith immediate tack or tackiness (often referred to as "tack") at room temperature, which makes it instantly tacky to the substrate under the action of brief light pressure. PSAs are widely used to produce self-adhesive labels or films as follows: these labels or films are affixed to articles for informational (such as bar code, name, price) and/or decorative purposes, whether temporarily affixed by adhesive or permanently affixed. PSAs are also used to produce self-adhesive tapes for various purposes. In addition to scotch tapes which are widely used in daily life, mention may be made, for example, of: forming and assembling of cardboard packaging; surface protection of paint engineering; securing and holding various items, such as panels, bricks, protruding objects, in the construction of a building or structure; fixing and holding metal, plastic or glass components, whether flat or with special profiles, such as cables, plastic films, window frames, sheets, inscriptions, signs, seat components, instrument panels, plastic or textile walls, pipes or tubes for conveying fluids, especially in the transport industry, gluing carpets by means of double-sided adhesive tape.

For the production of self-adhesive labels and/or tapes, the PSAs are usually applied in a certain amount (usually in g/m) by a continuous coating process²Meaning, hereinafter, with the term "weight per unit area") is applied to the entire surface of a large-sized carrier layer (which is suitably printable). The support layer is composed of a film or sheet or plate (having one or more layers) of paper or polymeric material. The adhesive layer covering the carrier layer may itself be covered with a protective non-stick layer (often referred to as a "release liner"), for example of an organosilicated film the resulting multilayer system is typically packaged by winding into large rolls up to 2m wide and at least 1m in diameter, which rolls may be stored and transported.

These multilayer systems can then be converted into self-adhesive labels that can be applied by the end user by conversion processes that include printing the desired information and/or decorative elements on the printable side of the carrier layer, and then cutting them into the desired shape and size. The release liner can be easily removed without altering the adhesive layer (keeping it fixed to the carrier layer). After separation from its release liner, the label is applied to the article to be affixed either by hand or using a labeling machine on an automated packaging line.

These multilayer systems can also be converted into self-adhesive tapes by cutting and packaging into rolls of defined width and length.

PSAs, due to their high room temperature tack, allow self-adhesive tapes and/or labels to be quickly held or attached to the substrate (or article) to be adhered (e.g., to a bottle in the case of a label, or to a cardboard carton to be formed in the case of a tape), suitable for achieving high industrial production speeds.

There are following fields of application of PSAs, it being desirable that the adhesion of labels and/or tapes on a substrate is still maintained when the adhesive joint providing the attachment (and thus the article to which the label and/or tape is to be affixed) is exposed to temperatures that can vary over a wide range. For example, it may be mentioned to place a label on some component of a motor vehicle (or other vehicle) located adjacent to the engine, or on a container designed to receive hot liquid during its packaging or even on an article (such as a tire) labeled under heat when leaving the production line. Mention may also be made of the use of self-adhesive tapes for assembling parts, for which case good heat resistance is necessary, such as in the case of interior trims for aircraft or other vehicles.

It can also be used to assemble surfaces that are not strictly parallel, or to bond self-adhesive articles to non-smooth surfaces such as surfaces with irregularities. A carrier layer which is referred to as "conformable" makes it possible to glue surface irregularities, for example by absorbing differences in thickness, but also to bond two surfaces which are not exactly parallel to one another, since deformations, curved surfaces or complex surfaces originating from the application of self-adhesive articles or the use of adhesive seams produced in this way require seams which are as adhesive as possible and thus withstand vibrations. After construction, the seam may also act as a general, local or temporary barrier to more or less abundant and frequent fluids.

Self-adhesive articles comprising such supports, which are called "conformable", can be used in many fields of application, such as:

-a motor vehicle: stickers for sticking signs, characters, internal sound insulation layers, internal decorations, in passenger compartments;

-construction: for sound and heat insulation, assembling windows;

-industrial: for assembly (assembly-fixing), for fixing photopolymer foils, such as those used in printers;

-furniture: for example for fixing mirrors;

-electronics: for fixing or stacking different constituent elements of the control or interface element.

International application WO 2011/082094 describes self-adhesive articles comprising a carrier layer in the form of a foam and an adhesive composition based on a polyacrylate modified by silylated functional groups. The polymers used in this document are solvent phase polymers. This document does not describe adhesive compositions for producing the self-adhesive articles according to the invention.

Application US 6,231,962 describes self-adhesive articles comprising a carrier layer in the form of a foam and an adhesive composition selected from the group consisting of olefins, organosilicated adhesives, natural rubber-based adhesives, synthetic rubber-based adhesives and other elastomer-based adhesives. The adhesive composition described in this document has a problem of high temperature resistance, and thus does not have satisfactory shear strength. This document does not describe adhesive compositions for producing the self-adhesive articles according to the invention.

Application WO2009/106699 describes self-adhesive articles comprising an adhesive layer obtained from polyurethane. Application EP2336208 describes a self-adhesive article comprising an adhesive layer obtained from a polyether. Both applications describe self-adhesive articles using a rigid support of the polyethylene terephthalate (PET) type.

Neither of these applications describes self-adhesive articles comprising the claimed support, nor the specific mixture of at least two polymers as claimed in the present invention.

The compliant carrier is stretchable and typically has a low density. Thus, this type of carrier is deformable and can be easily broken. In particular, the foam has a bubble structure, such as an air-filled structure having a fine film, and thus it can be easily broken.

Not all adhesive compositions that are capable of producing self-adhesive articles comprising PET type carriers are capable of producing self-adhesive articles comprising compliant carriers and having satisfactory properties for the application in question, such as high shear strength and high breaking temperature of the adhesive joint.

Disclosure of Invention

A first subject of the invention relates to self-adhesive articles comprising a carrier layer coated with an adhesive layer, said carrier layer having an elongation at break of 50 to 1200% and 25 to 1200kg/m³The adhesive layer is obtained by crosslinking an adhesive composition comprising:

a) at least one polymer of formula (Ia) or at least one polymer of formula (IIa) or a mixture of at least two polymers selected from polyurethanes and polyethers having one, two or three mono-, di-or tri-alkoxysilane-type end groups, said mixture comprising at least one polymer corresponding to one of formulae (Ia), (IIa), (IIIa) and (IVa),

wherein:

when a polymer having two or three monoalkoxysilane-type end groups is present, the mixture comprises at most 15% by weight of the polymer, relative to the total weight of the mixture,

when a polymer having one mono-, di-or tri-alkoxysilane-type end group is present, the mixture comprises at most 15% by weight of the polymer, relative to the total weight of the mixture,

b) at least one tackifying resin, and

c) at least one crosslinking catalyst;

wherein

Said polymer of formula (Ia) is a polyurethane or polyether comprising two or three hydrolyzable end groups of the trialkoxysilane type and corresponding to the formula wherein the amount of silyl functional groups is less than or equal to 0.480meq/g of polymer:

；

said polymer of formula (IIa) is a polyurethane or polyether comprising two or three hydrolyzable end groups of the dialkoxysilane type and corresponding to the formula below, in which the amount of silyl functional groups is less than or equal to 0.480meq/g of polymer:

；

the polymer of formula (IIIa) is a polyurethane or polyether comprising two or three monoalkoxysilane-type hydrolysable end groups and corresponding to the formula wherein the amount of silyl functional groups is less than or equal to 0.480meq/g of polymer:

；

said polymer of formula (IVa) is a polyurethane or polyether comprising one hydrolysable end group of the mono-, di-and/or trialkoxysilane type and corresponding to the formula wherein the amount of silyl functional groups is less than or equal to 0.480meq/g of polymer:

(ii) a In the above formulae (Ia), (IIa), (IIIa) and (IVa),

-B represents one of the following two formulae:

or

，

Wherein D and T represent a linear, branched, cyclic, alicyclic or aromatic, saturated or unsaturated hydrocarbon radical comprising from 2 to 66 carbon atoms, optionally comprising one or more heteroatoms,

-R¹denotes a divalent hydrocarbon radical comprising from 5 to 15 carbon atoms, which may be aromatic or aliphatic, linear, branched or cyclic,

-R³represents a linear or branched divalent alkylene group containing 1 to 6 carbon atoms,

-R²represents a linear or branched divalent alkylene group containing 2 to 4 carbon atoms,

-R⁴and R⁵Identical or different, each represents a linear or branched alkyl radical comprising from 1 to 4 carbon atoms, R⁴Optionally can be part of a ring that is,

-R⁶denotes a linear, branched, cyclic, alicyclic or aromatic, saturated or unsaturated hydrocarbon radical containing from 1 to 22 carbon atoms, optionally containing one or more heteroatoms,

-R⁷represents a hydrogen atom, a phenyl group or a linear, branched or cyclic alkyl group containing 1 to 10 carbon atoms,

n is such that formula- [ OR ]²]_nThe polyether blocks of (A) have an average molar mass of from 300g/mol to 40000g/mol,

-m is an integer such that the average molar mass of the polymer is between 600g/mol and 100000g/mol,

-p is an integer equal to 0, 1 or 2,

-f is an integer equal to 2 or 3.

According to one embodiment, the mixture of at least two polymers comprises:

at least one polymer corresponding to one of the above-mentioned formulae (Ia), (IIa), (IIIa) or (IVa), and

-at least one polymer corresponding to one of the following formulae (I), (II), (III) or (IV):

，

wherein:

-when a polymer of formula (IIIa) and/or (III) is present, the mixture comprises at most 15% by weight of polymer of formula (IIIa) and/or (III), relative to the total weight of the polymer mixture,

-when a polymer of formula (IVa) and/or (IV) is present, the mixture comprises at most 15% by weight of polymer of formula (IVa) and/or (IV), relative to the total weight of the polymer mixture;

in the above formulae (II), (IIa), (III) and (IV):

-B represents one of the following two formulae:

or

，

-p is an integer equal to 0, 1 or 2,

-f is an integer equal to 2 or 3.

Preferably the carrier layer has a young's modulus of less than or equal to 300 MPa.

According to one embodiment of the invention, the carrier layer is in the form of a foam.

According to one embodiment of the invention, the carrier layer has the form of one or more polymer layers.

Preferably the adhesive composition comprises:

-20-85% by weight, relative to the total weight of the adhesive composition, of at least one polymer or polymer mixture as defined in the present invention,

-15-80 wt.%, relative to the total weight of the adhesive composition, of at least one tackifying resin,

-0.01-3 wt% of at least one crosslinking catalyst, relative to the total weight of the adhesive composition.

Preferably the tackifying resin has a number average molar mass of from 100Da to 5kDa and is selected from:

(i) resins obtainable by the polymerization of terpene hydrocarbons and phenol in the presence of Friedel-Crafts catalysts,

(ii) a resin obtainable by polymerization of α -methylstyrene,

(iii) rosin of natural or modified origin,

(iv) resins obtained by hydrogenation, polymerization or copolymerization of a mixture of unsaturated aliphatic hydrocarbons having about 5, 9 or 10 carbon atoms derived from petroleum fractions,

(v) terpene resins typically resulting from the polymerization of terpene hydrocarbons in the presence of a friedel-crafts catalyst,

(vi) copolymers based on natural terpenes, and

(vii) an acrylic resin.

Another subject of the invention relates to a polymer mixture suitable for use in the adhesive composition as defined above, said mixture comprising at least two polymers belonging to two different groups selected from the group consisting of P1, P2, P3 and P4, said mixture comprising at least one polymer corresponding to one of the formulae (Ia), (IIa), (IIIa) and (IVa) and having an amount of silyl functions less than or equal to 0.480meq/g of polymer,

wherein:

-when the polymer of group P3 is present, the mixture comprises at most 15% by weight, relative to the total weight of the mixture, of at least one polyurethane or at least one polyether of group P3;

-when a polymer of group P4 is present, the mixture comprises at most 15% by weight, relative to the total weight of the polymer mixture, of at least one polyurethane or at least one polyether of group P4;

p1 is a group consisting of polyurethanes and polyethers with two or three trialkoxysilane-type end groups;

p2 is a group consisting of polyurethanes and polyethers with two or three dialkoxysilane-type end groups;

p3 is a group consisting of polyurethanes and polyethers with two or three monoalkoxysilane-type end groups;

p4 is a group consisting of polyurethanes and polyethers having one mono-, di-or tri-alkoxysilane-type end group.

According to one embodiment of the invention, the polymer mixture comprises:

-up to 95% by weight, relative to the total weight of the mixture, of at least one polymer corresponding to formula (Ia), and

-at least one polymer according to claim 1 corresponding to formula (IIa).

According to one embodiment of the invention, the polymer mixture comprises, relative to the total weight of the mixture of at least two polymers:

-10-85% by weight of at least one polymer corresponding to formula (Ia), and

15-90% by weight of at least one polymer corresponding to formula (IIa).

According to one embodiment of the invention, the polymer mixture comprises:

-up to 15% by weight, relative to the total weight of the mixture, of at least one polymer corresponding to formula (IIIa), and

-at least one polymer according to claim 1 corresponding to formula (IIa).

According to one embodiment of the invention, the polymer mixture comprises, relative to the total weight of the mixture:

-5 to 95% by weight of at least one polymer corresponding to formula (Ia), and

-5-15% by weight of at least one polymer corresponding to formula (IIIa).

According to one embodiment of the invention, the polymer mixture comprises:

-at least one polymer corresponding to one of the above formulae (I), (II), (III) or (IV).

The invention also relates to an adhesive composition suitable for producing the self-adhesive article according to the invention, comprising:

-a polymer mixture according to the invention,

-at least one tackifying resin, and

-at least one crosslinking catalyst.

Preferably, the adhesive composition according to the invention comprises:

-20-85 wt% of the polymer mixture, relative to the total weight of the adhesive composition,

The advantages of the invention are as follows:

the self-adhesive articles according to the invention have excellent adhesive strength and adhesive properties;

the self-adhesive article according to the invention has a high shear strength;

the self-adhesive article according to the invention allows the adhesive joint resulting from its attachment to the substrate to maintain the required cohesion over a large temperature range;

the self-adhesive articles according to the invention can be applied to many surfaces, such as concrete, plastic or metallic materials, motor vehicle bodies and painted materials;

the presence of the carrier layer in the self-adhesive article according to the invention makes it possible to bond the self-adhesive article to all types of surfaces, in particular surfaces with irregularities;

the self-adhesive article according to the invention makes it possible to glue surface irregularities, although the two surfaces to be bonded are not parallel;

the self-adhesive article according to the invention can be applied to a complex curved surface;

the self-adhesive article according to the invention ensures good thermal and acoustic insulation due to the nature of the carrier layer, in particular due to the carrier layer in the form of foam.

Detailed Description

Self-adhesive article

The invention relates to a coating comprisingSelf-adhesive article with an adhesive layer carrier layer having an elongation at break of 50 to 1200% and 25 to 1200kg/m³The adhesive layer is obtained by crosslinking an adhesive composition comprising:

wherein:

b) at least one tackifying resin, and

c) at least one crosslinking catalyst.

；

；

；

said polymer of formula (IVa) is a polyurethane or polyether comprising one end group of the mono-, di-and/or hydrolysable trialkoxysilane type and corresponding to the formula wherein the amount of silyl functions is less than or equal to 0.480meq/g of polymer:

；

in the above formulae (Ia), (IIa), (IIIa) and (IVa),

-B represents one of the following two formulae:

or

，

-R⁴and R⁵Identical or different, each represents a linear or branched alkyl radical comprising from 1 to 4 carbon atoms, R⁴Optionally as part of a ring, which is,

-R⁶denotes a straight-chain, branched, cyclic ring containing from 1 to 22 carbon atomsA cyclic, alicyclic or aromatic, saturated or unsaturated hydrocarbon radical optionally containing one or more heteroatoms,

-p is an integer equal to 0, 1 or 2,

-f is an integer equal to 2 or 3.

In case the adhesive composition comprises at least two polymers of different formulae, B, R is defined above¹、R²、R³、R⁴、R⁵、R⁶Each parameter of n, m, p and f can be independently selected in each formula, i.e. they may be the same or different in each polymer.

For example, B may have the following structure (in this example, f would equal 2):

or the following structure (in this example, f would then equal 3):

。

for example, R⁶May be a methyl group.

Preferably R¹Selected from one of the following divalent groups, 2 free valences being represented in the following formula:

a) divalent group derived from isophorone:

b)

c)

or

d)

Or

e) -(CH₂)₆- (or 1, 6-hexylene).

Support layer

The carrier layer has an elongation at break of 50-1200%, preferably 100-1000%, even more preferably 200-700%, and 25-1200kg/m³Preferably 25 to 1000kg/m³Even more preferably 25-900kg/m³Even more preferably from 32 to 800kg/m³Even more preferably 50-600kg/m³Even more preferably from 60 to 400kg/m³The bulk density of (c).

The elongation at break can be measured according to standard ISO 1926 at 23 ℃ in the length direction or in the width direction. The elongation is preferably measured in the length direction.

Bulk density can be measured according to standard ISO 845.

The filler can be added during the production of the support layer to obtain a support layer having a mass of greater than or equal to 1000kg/m³A bulk density carrier layer of (a). One skilled in the art knows how to increase the bulk density of a material while maintaining the desired elongation at break properties.

Preferably the carrier layer has a young's modulus lower than or equal to 300MPa, preferably of from 2 to 100MPa, even more preferably of from 5 to 50MPa, more particularly of from 5 to 35 MPa.

Preferably the support layer has a thickness of 0.01-50mm, even more preferably 0.01-20.00mm, preferably 0.05-10.00mm, even more preferably 0.05-1.00mm, advantageously 0.10-0.75 mm.

Preferably the carrier layer is in the form of a foam.

Within the meaning of the present invention, a foam is a polymeric material comprising gas-filled cells. The foam may have open or closed cells, and the structure of the foam depends on the method by which the foam is expanded.

Preferably, the outer surface of the carrier that is in contact with the adhesive composition is closed, i.e. the pores on the surface in contact with the adhesive composition are all closed pores.

Preferably the entire carrier layer is a closed cell foam.

According to a first embodiment, the carrier layer is made of a material selected from the group consisting of:

polyolefins, such as polyethylene, including high density polyethylene, low density polyethylene, linear low density polyethylene and linear ultra low density polyethylene, polypropylene and polybutylene;

-polystyrene;

-natural or synthetic rubber;

vinyl copolymers, such as plasticized or unplasticized polyvinyl chloride, and polyvinyl acetate;

olefin copolymers such as ethylene-methacrylate copolymers, ethylene/vinyl acetate copolymers, acrylonitrile/butadiene/styrene copolymers and ethylene/propylene copolymers;

-a polymer and an acrylic copolymer;

-a polyurethane;

-a polyether;

-a polyester; and

mixtures thereof.

Preferably the carrier layer comprises a mixture of elastomeric and/or plastic materials such as polypropylene/polyethylene, polyurethane/polyolefin, polyurethane/polycarbonate, polyurethane/polyester.

Preferably the carrier layer is in the form of one or more layers of polymer foam, preferably polyolefin foam.

Among the foams that can be used to form the carrier layer of the self-adhesive article according to the invention, mention may be made of:

-TL SRZ 1200.8 foam (available from Alveo) having elongation at break of 408.8. + -. 53% at 23 ℃ of about 96.62kg/m³A bulk density of about 0.67mm, a thickness of about 0.67mm and a young's modulus of 11.2 ± 0.5 MPa;

TEE 0400.2 foam (commercially available from Alveo) having an elongation at break of 362.5. + -. 85% at 23 ℃ of about 293kg/m³A bulk density of about 0.17mm, a thickness of about 0.6MPa and a Young's modulus of 18.3. + -. 0.6 MPa;

-TMA SRZ 0500.8 foam (available from Alveo) having an elongation at break of 717.5. + -. 117% at 23 ℃ of about 196.31kg/m³A bulk density of about 0.72mm, a thickness of about 0.7 ± 0.8MPa and a young's modulus of 6.7; and

-TL SRZ 0700.8 foam (available from Alveo) having an elongation at break of 635.4. + -. 76% at 23 ℃ of about 148.15kg/m³A bulk density of about 0.76mm, a thickness of about 0.76mm and a young's modulus of 12.9 ± 0.8 MPa.

According to one embodiment of the invention, the carrier layer is a syntactic foam. The technique of syntactic foams is described, for example, in Klempner et al, Polymeric Foam Technology, second edition, Hanser (2004), page 479.

Applying the adhesive composition to the carrier to produce a self-adhesive article.

The adhesive-free back of the two sides of the carrier layer can be covered by a release liner, for example an organosilicate film. In this way, the self-adhesive article can be rolled up on itself and subsequently unrolled without any problem due to the lack of adhesion of the adhesive layer to the siliconized surface.

The support layer according to the invention can also be treated with all types of surface treatment, such as corona treatment, making it possible in particular to increase the wettability.

Adhesive composition

The adhesive layer is obtained by crosslinking the adhesive composition.

As indicated above, the carrier layer can also be obtained by expanding a base material comprising the adhesive composition according to the invention to obtain a foam known as syntactic foam.

The adhesive composition used in the self-adhesive article of the invention comprises:

a) as described below for the polymer or polymer mixture of the self-adhesive article,

b) at least one kind of tackifying resin,

c) at least one crosslinking catalyst.

According to one embodiment, the adhesive composition used in the self-adhesive article of the invention consists essentially of:

b) at least one tackifying resin, and

c) at least one crosslinking catalyst.

The polymer may be a polymer of formula (Ia) or a polymer of formula (IIa).

The mixture of at least two polymers present in the adhesive composition used for producing the self-adhesive article comprises at least two different polymers selected from polyurethanes and polyethers having one, two or three mono-, di-or tri-alkoxysilane-type end groups, said mixture comprising at least one polymer of formula (Ia), (IIa), (IIIa) or (IVa).

When a polymer having two or three monoalkoxysilane-type end groups is present in the mixture of the at least two polymers, the mixture comprises at most 15% by weight of the polymer, relative to the total weight of the mixture.

When a polymer having one mono-, di-or tri-alkoxysilane-type end group is present in the mixture of the at least two polymers, the mixture comprises at most 15% by weight of the polymer relative to the total weight of the mixture.

The amount of silyl functions is given by the supplier or can be determined by analysis (NMR), or it can be determined as a function of the content (% by weight) and the nature (chemical structure and molar mass) of the aminosilane used for the synthesis of the polymers (Ia), (IIa), (IIIa) and (IVa).

The polymer corresponding to one of the formulae (Ia), (IIa), (IIIa) and (IVa) can be obtained according to the process as described in the experimental part of the present invention, wherein, optionally, in the polymer (IVa), the polyether diol is replaced wholly or partly by a polyether monool.

The polymers or polymer mixtures preferably used for the production of the self-adhesive articles according to the invention have a number-average molar mass of 600-.

The number average molar mass (Mn) in g/mol is calculated from the amount of silyl functional groups (E (s)) in meq/g and the polymer functionality F.

For the polymers of formulae (Ia), (IIa) and (IIIa), the functionality F is equal to 2 or 3.

For the polymer of formula (IVa), the functionality F is equal to 1.

The number average molar mass is calculated as follows:

。

among the polymers according to the invention corresponding to formula (Ia), mention may be made of the polymers Ex19 and Ex20 described in the experimental section.

Among the polymers according to the invention corresponding to formula (IIa), mention may be made of the polymers Ex8 and Ex6-18 described in the experimental section.

Among the polymers according to the invention corresponding to formula (IIIa), mention may be made of the polymer Ex15 described in the experimental section.

Preferably all polymers or polymer mixtures which can be used for producing the self-adhesive articles according to the invention have an amount of silyl functional groups of less than or equal to 0.480meq/g of polymer, preferably less than or equal to 0.450meq/g of polymer.

According to one embodiment, the mixture of at least two polymers comprises at least two polymers selected from the group of polymers of formulae (Ia), (IIa), (IIIa) and (IVa).

According to another embodiment, the mixture of at least two polymers comprises at least a polyurethane or polyether having one, two or three mono-, di-or tri-alkoxysilane-type end groups, different from the polyurethane and polyether of formula (Ia), (IIa), (IIIa) or (IVa).

Preferably, said polyurethanes or said polyethers having one, two or three mono-, di-or tri-alkoxysilane-type end groups, which are different from the polyurethanes and polyethers of formula (Ia), (IIa), (IIIa) or (IVa), are selected from:

-a polyurethane or polyether comprising two or three hydrolyzable end groups of the dialkoxysilane type and corresponding to formula (II):

；

-polyurethanes or polyethers containing two or three hydrolysable end groups of the trialkoxysilane type and corresponding to formula (I):

(I)；

-a polyurethane or polyether comprising two or three mono-alkoxysilane type hydrolysable end groups and corresponding to formula (III):

;

-polyurethanes or polyethers containing one hydrolysable end group of the mono-, di-and/or tri-alkoxysilane type and corresponding to formula (IV):

。

in the above formulae (I), (II), (III) and (IV),

-B represents one of the following two formulae:

or

，

Wherein D and T represent a hydrocarbon radical comprising from 2 to 66 carbon atoms, linear, branched, cyclic, alicyclic or aromatic, saturated or unsaturated, optionally comprising one or more heteroatoms such as oxygen, sulphur, nitrogen or halogen,

-R²represents a linear or branched divalent alkylene group containing 2 to 4 carbon atoms and preferably 3 carbon atoms,

-R⁶denotes a hydrocarbon radical comprising from 1 to 22 carbon atoms, linear, branched, cyclic, alicyclic or aromatic, saturated or unsaturated, optionally comprising one or more heteroatoms such as oxygen, sulfur, nitrogen or halogen,

-p is an integer equal to 0, 1 or 2,

-f is an integer equal to 2 or 3.

The polymer corresponding to one of formulae (I), (II), (III) and (IV) may be obtained according to the process described in applications EP2336208 and WO2009/106699, wherein the polyether diol is optionally replaced in whole or in part by a polyether monol in the polymer of formula (IV).

According to one embodiment, the mixture of the at least two polymers used for producing the self-adhesive article comprises, relative to the total weight of the polymer mixture:

5-95% by weight, preferably 10-90% by weight, of at least one polymer selected from polymers of the formulae (Ia), (IIa), (IIIa), (IVa); and

-5-95% by weight, preferably 10-90% by weight, of at least one other silylated polymer preferably selected from polymers of formula (I), (II), (III) or (IV).

According to one embodiment, the tackifying resin has a number average molar mass of between 100Da and 5kDa, preferably between 500Da and 4 kDa.

According to one embodiment, the tackifying resin is selected from:

(i) resins obtainable by the polymerization of terpene hydrocarbons and phenol in the presence of a Friedel-crafts catalyst,

(ii) resins obtainable by polymerization of α -methylstyrene and optionally by reaction with phenol,

(iii) rosins of natural or modified origin, such as rosins extracted from pine resin, wood rosins extracted from roots of trees and their hydrogenated, dimerized, polymerized or esterified by mono-or polyhydric alcohols, such as glycerol;

(iv) resins obtained by hydrogenation, polymerization or copolymerization (with aromatic hydrocarbons) of a mixture of unsaturated aliphatic hydrocarbons having about 5, 9 or 10 carbon atoms derived from petroleum fractions;

(v) terpene resins produced by the polymerization of terpene hydrocarbons such as mono-terpene (or pinene), typically in the presence of a friedel-crafts catalyst;

(vi) copolymers based on natural terpenes, such as styrene-terpene, α -methylstyrene-terpene and vinyltoluene-terpene, and

(vii) an acrylic resin.

Such resins are commercially available and, according to those of types (i), (ii) and (iii) defined above, the following products may be mentioned:

(i) resin type: dertophene 1510 available from DRT having a number average molar mass, Mn, of about 870 Da; dertophene HI 50, commercially available from the same company, having a molar weight Mn of about 630 Da; sylvarez TP 95, commercially available from Arizona Chemical having a number average molar mass, Mn, of about 1200 Da;

(ii) sylvarez 510, also available from Arizona Chemical, having a number average molar mass Mn of about 1740Da, further comprising adding phenol;

(iii) resin type: sylvalite RE 100, an ester of rosin and pentaerythritol, commercially available from Arizona chemical and having a number average molar mass of about 1700 Da.

The number average molar mass of the resin can be measured using methods well known to those skilled in the art, for example by size exclusion chromatography using polyethylene glycol standards.

According to a preferred variant, resins selected from those of type (i) or (ii) are used as tackifying resins.

According to another preferred variant, a resin of type (iii) and preferably a rosin ester is used as tackifying resin.

The crosslinking catalyst used in the adhesive composition according to the invention may be any catalyst known to the person skilled in the art for silanol condensation. Examples which may be mentioned as such catalysts are organic derivatives of titanium, such as titanium acetylacetonate (commercially available from DuPont under the name TYZOR AA 75); organic derivatives of aluminum, such as aluminum chelate (commercially available from King Industries under the name K-KAT 5218); organic derivatives of amines, such as 1, 8-diazabicyclo [5.4.0] undec-7-ene, DBU.

Preferably, the adhesive composition comprises less than 5 wt.%, preferably less than 3 wt.%, even more preferably less than 1 wt.%, ideally less than 0.5 wt.% of solvent relative to the total weight of the adhesive composition prior to crosslinking of the silylated functional groups.

Optionally, the composition according to the invention may also comprise thermoplastic polymers commonly used in the preparation of HMPSAs, such as ethylene-vinyl acetate (EVA) or styrene block copolymers, in combination with the above-mentioned polymers or polymer mixtures.

The adhesive composition may furthermore comprise up to 3% by weight of a hydrolysable alkoxysilane derivative, preferably a trimethoxysilane derivative, as a drying agent. Such agents advantageously extend the shelf life of the composition according to the invention during storage and transport prior to use. Mention may be made, for example, of gamma-methacryloxypropyltrimethoxysilane, commercially available under the trade name SILQUEST A-174 from USMomentive Performance Materials Inc.

The composition according to the invention may also comprise a plasticizer such as phthalate or benzoate esters, paraffin and naphthenic oils (such as Primol 352 from ESSO) or also polyethylene homopolymer wax (such as A-C617 from Honeywell) or polyethylene and vinyl acetate copolymer wax, or also pigments, colorants or fillers.

Finally, one or more stabilizers (or antioxidants) are preferably included in the composition according to the invention in an amount of 0.1 to 2% by weight. These compounds are introduced to protect the composition from degradation by reaction with oxygen, which may be caused by the action of heat or light. These compounds may include primary antioxidants, which trap free radicals and which are in particular substituted phenols, such as Irganox 1076 from CIBA. The primary antioxidant may be used alone or in combination with other secondary antioxidants or uv stabilizers.

According to one embodiment, the adhesive composition comprises, relative to the total weight of the adhesive composition:

a)20 to 85 wt.%, preferably 40 to 65 wt.%, of a polymer or polymer mixture as described above,

b) 15-80% by weight, preferably 25-70% by weight, preferably 35-60% by weight, of a tackifying resin, and

c)0.01 to 3 wt% of a crosslinking catalyst.

According to one embodiment, the adhesive composition consists essentially of, relative to the total weight of the adhesive composition:

c)0.01 to 3 wt% of a crosslinking catalyst.

The thermally crosslinkable adhesive composition for producing the self-adhesive article according to the invention can be prepared by a process comprising:

-a step of mixing the polymer or polymer mixture with the tackifying resin in the absence of air, preferably under an inert atmosphere at a temperature between 30-170 ℃, preferably between 100-170 ℃, followed by a step of cooling the mixture to a temperature of 30-90 ℃ and advantageously about 70 ℃, followed by a step of cooling the mixture

-a step of adding the crosslinking catalyst to the mixture obtained in the preceding step and, if appropriate, a drying agent and other optional ingredients.

According to one embodiment of the invention, the adhesive layer has a loop tack (loop tack) of at least 0.75N/cm, preferably at least 0.80N/cm, even more preferably at least 0.90N/cm, ideally at least 1N/cm after at least partial crosslinking of the silylated functional groups, preferably no residue, as measured on a glass plate.

According to one embodiment of the invention, the adhesive layer as described above may have a loop tack of at least 5N/cm, preferably at least 6N/cm, even more preferably at least 7N/cm, ideally at least 8N/cm. According to one embodiment, the adhesive composition according to the invention may have a loop tack of from 0.75 to 8N/cm, preferably from 0.80 to 7N/cm, even more preferably from 0.90 to 6N/cm, ideally from 1 to 5N/cm. The loop tack may be obtained immediately after bonding the article to the surface and/or several hours after bonding the article to the surface and/or several days after bonding the article to the surface.

Within the meaning of the present invention, the term "self-adhesive article" includes any article that can be adhered to a surface by the action of manual or mechanical pressure alone, without the use of other glues or adhesives. The expression "self-adhesive article" also includes the expression "pressure-sensitive adhesive" article or "PSA" article. The purpose of these articles would be to be applied on the surfaces to be bonded so as to be closely together, held, fixed, or simply immobilized to indicate a shape, logo, image, or information. These articles can be used in many fields, such as the medical field, clothing, packaging, motor vehicles or buildings, in particular thanks to excellent thermal and acoustic insulation properties. They may be formed according to their end use, for example in the form of tapes, such as tapes for industrial use, tapes for DIY use or for fixing on building sites, single-or double-sided tapes, or in the form of labels, bandages, dressings, patches or graphic films.

The self-adhesive articles according to the invention can be applied to surfaces with irregularities, curved or complex surfaces, or also to surfaces which are deformable or have deformations. The article according to the invention may make it possible to bond two surfaces that are not strictly flat. In particular, the surfaces to be bonded may have properties comparable to those of the carrier layer.

The surface to be bonded may be selected from the group consisting of plastic, concrete, steel, glass, cardboard, skin, fabric, foam. The surface may or may not be painted.

According to one embodiment of the invention, the self-adhesive article further comprises a non-stick protective release liner ("release liner").

According to one embodiment, the release liner is applied to the adhesive layer after crosslinking the adhesive composition.

According to a first embodiment, the self-adhesive article according to the invention can be prepared by a process comprising the following steps:

(a) conditioning the adhesive composition as previously defined at a temperature of 20-160 ℃; followed by

(b) Applying the adhesive composition obtained in step (a) to a support surface; followed by

(c) Crosslinking the coated adhesive composition by heating the coated support surface at a temperature of 20-200 ℃;

optionally, optionally

(d) Laminating or transferring the crosslinked adhesive layer to a support layer or a non-stick protective film.

By "support surface" within the meaning of the present invention is meant a conveyor belt, or a release liner, or a carrier layer, covered with a non-stick layer.

In the case where the support surface is not a carrier layer, the process for obtaining the self-adhesive article according to the invention comprises a step (d) of transferring the crosslinked adhesive layer onto a carrier layer.

In the case where the support surface is a carrier layer, the process for obtaining the self-adhesive article according to the invention may comprise a step (d) of laminating the crosslinked adhesive layer to a non-stick protective film.

According to one embodiment, the process for producing the self-adhesive article according to the invention further comprises a step (e) of applying a layer of a second adhesive composition onto the carrier layer, followed by a step (f) of crosslinking the adhesive composition applied in step (e) by heating at a temperature of 20 to 200 ℃. According to this embodiment, a double-sided self-adhesive article is obtained.

The coating step (b) may be performed using a known coating device such as a lip type or curtain type nozzle or also a roll. It is used in an amount of 3 to 2000g/m²Preferably 5 to 500g/m²Even more preferably from 10 to 250g/m²Per unit area of the adhesive composition.

Preferably the coating is continuous or substantially continuous.

According to one embodiment, during step (c), the coated adhesive composition is furthermore subjected to a treatment in a humid atmosphere characterized by its moisture content. Preferably the humid atmosphere is an atmosphere in which 2-100% of the molecules are water molecules, preferably 4-50%, even more preferably 5-10% of the molecules are water molecules.

The moisture content is expressed as a percentage of water per unit volume, which corresponds to the number of water molecules in a unit volume divided by the total number of molecules. Due to the linear nature of the scale, the moisture content can be easily measured and controlled by using, for example, a p.i.d (proportional-integral-derivative) type monitor. The weight percent can be calculated by multiplying the percentage of water molecules relative to the total number of molecules by a factor of 0.622. General information on moisture content in various environments is available from Wagner et al "International

Steam Tables-Properties of Water and Steam based on the Industrial Formula IAPWS-IF9T"is described herein.

The time required for the crosslinking step (c) may vary within wide limits, for example from 1 second to 10 minutes, depending on the weight per unit area of the adhesive composition deposited on the support surface, the heating temperature and the moisture.

This thermal crosslinking step causes the creation of siloxane-type bonds between the polymer chains of the polymer or polymer mixture as described above and under the action of moisture, which leads to the formation of a three-dimensional polymer network. The adhesive composition crosslinked in this manner is a pressure-sensitive adhesive that imparts the desired adhesive force and tack on the support coated therewith.

Preferably the coating is carried out uniformly on the carrier layer or on the release liner, but the coating can also be adapted to the desired shape of the final self-adhesive article.

According to one embodiment, the coating of the adhesive composition is performed on at least a part of both sides of the carrier layer. If both sides of the carrier layer are coated, the adhesive composition may be the same or different on both sides, and the weight per unit area may be the same or different on both sides.

According to one embodiment of the invention, the self-adhesive article comprises an adhesive layer on at least a portion of one or both sides of the carrier layer, the adhesive layer optionally being coated with a release liner. According to one embodiment, the self-adhesive article comprises two release liners on each of the two adhesive layers. In this case, the two protective layers may be made of the same or different materials and/or they may have the same or different thicknesses.

The self-adhesive article according to the invention can be used in a bonding process comprising the following steps:

a) removing the non-stick protective film (release liner) when present;

b) applying the article to a surface; and

c) applying pressure to the article.

According to one embodiment, wherein the self-adhesive article is a double-sided article, the bonding method further comprises a step wherein a second surface is applied to the article bonded to the first surface or the article bonded to the first surface is applied to the second surface.

Mixtures of at least two polymers

The invention also relates to a mixture of at least two polymers which can be added to the adhesive composition for producing the self-adhesive articles according to the invention. The mixture of at least two polymers according to the invention comprises at least two polymers belonging to 2 different groups selected from the groups P1, P2, P3 and P4, it being understood that at least one of these two polymers of the mixture corresponds to one of the formulae (Ia), (IIa), (IIIa) or (IVa).

As stated above for the self-adhesive articles, the polymers of formulae (Ia), (IIa), (IIIa) and (IVa) according to the invention have an amount of silyl functional groups of less than or equal to 0.480meq/g of polymer, preferably less than or equal to 0.450meq/g of polymer.

Preferably all polymers of the mixture of at least two polymers have a silyl functional group content of less than or equal to 0.480meq/g of polymer, preferably less than or equal to 0.450meq/g of polymer.

Preferably the polymer mixture according to the invention has an average molar mass of 600-.

These groups are defined as follows:

○ group P1 polyurethanes or polyethers having two or three trialkoxysilane-type end groups, examples being polymers corresponding to the formula (Ia) or (I);

○ group P2 polyurethanes or polyethers having two or three dialkoxysilane-type end groups, examples being polymers corresponding to the formula (IIa) or (II);

○ group P3 polyurethanes or polyethers having two or three monoalkoxysilane-type end groups, examples being polymers corresponding to the formulae (IIIa) or (III);

○ group P4 polyurethanes or polyethers having one terminal group of the mono-, di-or trialkoxysilane type, examples being polymers corresponding to the formula (IVa) or (IV).

When a polymer belonging to group P1 is present in the mixture of at least two polymers according to the invention, the mixture comprises at most 99% by weight, relative to the total weight of the mixture, of one or more polymers of group P1.

When a polymer belonging to group P2 is present in the mixture of at least two polymers according to the invention, the mixture comprises at most 99% by weight, relative to the total weight of the mixture, of one or more polymers of group P2.

When a polymer belonging to group P3 is present in the mixture of at least two polymers according to the invention, the mixture comprises at most 15% by weight, relative to the total weight of the mixture, of one or more polymers of group P3.

When a polymer belonging to group P4 is present in the mixture of at least two polymers according to the invention, the mixture comprises at most 15% by weight, relative to the total weight of the mixture, of one or more polymers of group P4.

Preferably the mixture of at least two polymers comprises predominantly polymers of groups P1, P2, P3 and P4. It is preferred that the mixture of at least two polymers according to the invention does not comprise polymers other than those belonging to the groups P1, P2, P3 and P4.

According to a first embodiment of the invention, the mixture of at least two polymers comprises:

-at most 95% by weight, relative to the total weight of the polymer mixture, of at least one polymer belonging to group P1, and

-at least one polymer belonging to group P2.

According to this embodiment, it is preferred that the mixture of at least two polymers comprises, relative to the total weight of the mixture of at least two polymers:

10-95% by weight, preferably 20-90% by weight, even more preferably 25-85% by weight, advantageously 30-75% by weight, of at least one polymer belonging to group P1, and

5-90% by weight, preferably 10-80% by weight, even more preferably 15-75% by weight, advantageously 25-70% by weight, of at least one polymer belonging to group P2.

According to this embodiment of the invention, it is preferred that the mixture of at least two polymers consists essentially of:

-at least one polymer belonging to group P2.

According to this embodiment, it is preferred that the mixture of at least two polymers consists essentially of, relative to the total weight of the mixture of at least two polymers:

According to a second embodiment of the invention, the mixture of at least two polymers comprises:

-at most 15% by weight, relative to the total weight of the polymer mixture, of at least one polymer belonging to group P3.

-5-15% by weight, preferably 7-15% by weight, even more preferably 9-12% by weight, of at least one polymer belonging to group P3.

According to a third embodiment of the invention, the mixture of at least two polymers comprises:

-at least one polymer belonging to group P2, and

85 to 99% by weight, preferably 87 to 97% by weight, even more preferably 90 to 95% by weight, of at least one polymer belonging to group P2, and

1-15% by weight, preferably 3-13% by weight, even more preferably 5-10% by weight, of at least one polymer belonging to group P3.

-at least one polymer belonging to group P2, and

According to a fourth embodiment of the invention, the mixture of at least two polymers comprises:

-at most 15% by weight, relative to the total weight of the polymer mixture, of at least one polymer belonging to group P4.

-5-15% by weight, preferably 7-15% by weight, even more preferably 9-12% by weight, of at least one polymer belonging to group P4.

According to a fifth embodiment of the invention, the mixture of at least two polymers comprises:

-at least one polymer belonging to group P2, and

1-15% by weight, preferably 3-13% by weight, even more preferably 5-10% by weight, of at least one polymer belonging to group P4.

-at least one polymer belonging to group P2, and

According to one embodiment of the invention, the mixture of at least two polymers comprises:

-up to 95% by weight, relative to the total weight of the polymer mixture, of at least one polymer corresponding to formula (Ia), and

-at least one polymer corresponding to formula (IIa).

10 to 95% by weight, preferably 20 to 90% by weight, even more preferably 25 to 85% by weight, advantageously 30 to 75% by weight, of at least one polymer corresponding to formula (Ia), and

5-90% by weight, preferably 10-80% by weight, even more preferably 15-75% by weight, advantageously 25-70% by weight, of at least one polymer corresponding to formula (IIa).

-at least one polymer corresponding to formula (IIa).

According to this embodiment of the invention, it is preferred that the mixture of at least two polymers consists essentially of, relative to the total weight of the mixture of at least two polymers:

According to another embodiment of the invention, the mixture of at least two polymers comprises:

-up to 15% by weight, relative to the total weight of the polymer mixture, of at least one polymer corresponding to formula (IIIa).

According to this embodiment of the invention, it is preferred that the mixture of at least two polymers comprises, relative to the total weight of the mixture of at least two polymers:

5-15% by weight, preferably 7-15% by weight, even more preferably 9-12% by weight, of at least one polymer corresponding to formula (IIIa).

at least one polymer corresponding to formula (IIa), and

from 85 to 99% by weight, preferably from 87 to 97% by weight, even more preferably from 90 to 95% by weight, of at least one polymer corresponding to formula (IIa), and

1-15% by weight, preferably 3-13% by weight, even more preferably 5-10% by weight, of at least one polymer corresponding to formula (IIIa).

at least one polymer corresponding to formula (IIa), and

-at most 15% by weight, relative to the total weight of the polymer mixture, of at least one polymer corresponding to formula (IVa).

-5-15% by weight, preferably 7-15% by weight, even more preferably 9-12% by weight, of at least one polymer corresponding to formula (IVa).

at least one polymer corresponding to formula (IIa), and

1-15% by weight, preferably 3-13% by weight, even more preferably 5-10% by weight, of at least one polymer corresponding to formula (IVa).

at least one polymer corresponding to formula (IIa), and

According to one embodiment, the mixture of at least two polymers comprises predominantly polymers corresponding to the above-mentioned formulae (Ia), (IIa), (IIIa) and (IVa). Preferably, the mixture of at least two polymers according to the invention does not comprise polymers other than those corresponding to the above-mentioned formulae (Ia), (IIa), (IIIa) and (IVa).

According to another embodiment, the mixture of at least two polymers comprises:

-at least one polymer corresponding to one of the formulae (Ia), (IIa), (IIIa) and (IVa), and

-at least one other silylated polymer belonging to one of the groups P1, P2, P3 and P4,

it is understood that said other silylated polymers do not belong to the same group as said polymers of formula (Ia), (IIa), (IIIa) or (IVa).

"other silylated polymers" means polymers different from the said formulae (Ia), (IIa), (IIIa) and (IVa)A polymer and comprising at least one monomer corresponding to the general formula: -Si (R)⁵)_p(OR⁴)_3-pThe silylated functional group of (A), wherein R⁵、R⁴And p has the same meaning as above.

Preferably, the one or more other silylated polymers are selected from:

-polyurethanes or polyethers belonging to group P2, comprising two or three hydrolyzable end groups of the dialkoxysilane type and corresponding to formula (II):

；

-polyurethanes or polyethers belonging to group P1, comprising two or three hydrolysable end groups of the trialkoxysilane type and corresponding to formula (I):

；

-polyurethanes or polyethers belonging to group P3, comprising two or three mono-alkoxysilane type hydrolysable end groups and corresponding to formula (III):

)；

-polyurethanes or polyethers belonging to group P4, containing one hydrolysable end group of the mono-, di-and/or tri-alkoxysilane type and corresponding to formula (IV):

。

in the above formulae (I), (II), (III) and (IV):

-B represents one of the following two formulae:

or

，

-R²represents a linear or branched divalent alkylene group containing 2 to 4 carbon atoms, preferably 3 carbon atoms,

- R⁶denotes a hydrocarbon radical comprising from 1 to 22 carbon atoms, linear, branched, cyclic, alicyclic or aromatic, saturated or unsaturated, optionally comprising one or more heteroatoms such as oxygen, sulfur, nitrogen or halogen,

-p is an integer equal to 0, 1 or 2,

-f is an integer equal to 2 or 3.

Preferably, the mixture of at least two polymers according to the invention comprises, relative to the total weight of the mixture of at least two polymers:

5-95% by weight, preferably 10-90% by weight, of at least one polymer corresponding to one of the formulae (Ia), (IIa), (IIIa) and (IVa); and

5-95% by weight, preferably 10-90% by weight, of at least one other silylated polymer preferably selected from polymers of formula (I), (II), (III) or (IV),

it is understood that the mixture comprises at least two polymers belonging to two different groups selected from the group of P1, P2, P3 and P4.

Adhesive composition

The invention also relates to an adhesive composition suitable for producing the self-adhesive article according to the invention.

The composition according to the invention comprises:

a) the mixture of at least two polymers according to the invention,

b) at least one tackifying resin, and

c) at least one crosslinking catalyst.

According to one embodiment, the adhesive composition according to the invention comprises, relative to the total weight of the adhesive composition:

a)20 to 85 wt.%, preferably 40 to 65 wt.%, of a mixture of at least two polymers according to the invention,

b)15-80 wt.%, preferably 25-70 wt.%, even more preferably 35-60 wt.% of a tackifying resin,

c)0.01 to 3 wt% of a crosslinking catalyst.

According to one embodiment, the adhesive composition according to the invention consists essentially of, relative to the total weight of the adhesive composition:

c)0.01 to 3 wt% of a crosslinking catalyst.

Preferably the tackifying resin is as described previously for the self-adhesive article according to the invention.

Preferably the crosslinking catalyst is as previously described for the self-adhesive article according to the invention.

According to one embodiment, the adhesive composition according to the invention further comprises one or more additives selected from desiccants, plasticizers, stabilizers (or antioxidants). Preferably these additives are as previously described for the self-adhesive article according to the invention.

The adhesive composition according to the present invention may be prepared by a method comprising:

-a step of mixing the mixture of said at least two polymers with said one or more tackifying resins in the absence of air, preferably under an inert atmosphere at a temperature between 30 and 170 ℃, preferably between 100 and 170 ℃, followed by a step of cooling the mixture to a temperature of between 30 and 90 ℃ and advantageously about 70 ℃, followed by a step of cooling the mixture

The adhesive composition according to the invention is not described in the prior art. The adhesive composition according to the invention can be used with a carrier layer different from the carrier layer described above for the self-adhesive article according to the invention.

The adhesive composition according to the invention can be used for producing self-adhesive articles comprising a temporary or permanent carrier and an adhesive layer obtained by crosslinking the adhesive composition.

The support of the self-adhesive articles obtained from the adhesive composition according to the invention can be a temporary or permanent support.

In the case where the support is a temporary support, the support is preferably a non-stick protective film ("release liner"). In this case, once the article is adhered to a surface, the adhered article will include only the adhesive layer and the temporary carrier will be removed.

In case the carrier is a permanent carrier, the carrier may be based on any material that can be used for producing Pressure Sensitive Adhesives (PSA), such as polypropylene, polyethylene, polyimide and paper. The carrier may be made of a fiber or plastic tape, a fabric, a metal fiber, or a glass fiber.

According to one embodiment, the support is based on polyethylene terephthalate (PET), polypropylene (PP) or Polyurethane (PU).

According to one embodiment of the invention, the support is in the form of a grid or mesh or a nonwoven material. In this case, the carrier layer may be present on one side of the carrier, but may also be penetrated within the carrier during application of the adhesive composition due to the porous nature of the carrier, so that the fibers of the carrier are completely coated with the adhesive composition. In this case, a non-stick protective film is preferably present on the adhesive layer or adhesive composition.

According to one embodiment, the self-adhesive article obtained from the adhesive composition according to the invention comprises a permanent support coated with an adhesive layer. Preferably, the adhesive layer is coated here with a non-stick protective film, preferably an organosilicate film.

As an alternative to a non-stick protective film, the back of the permanent carrier, which is not coated with an adhesive layer, may have a non-stick surface, for example an organosilicated protective layer.

Both embodiments described above make it possible to roll up the self-adhesive article and subsequently unroll it without the problem of adhesive transfer between the adhesive layer and the permanent carrier.

According to one embodiment, the permanent support is coated on both sides with an adhesive composition, which may be the same or different, at least one of the two being an adhesive composition according to the invention.

The carrier may be prepared from the following materials:

polyurethane Material Estane. 58309NAT022 (B.F. Goodrich, Cleveland, Ohio),

polyurethane Rucothane ™ or polyester elastomer HytreFM 4056 (DuPont, Wilmington, Del),

polyether Block amides Pebax 2533 or 3533 (Arkema, Paris, France).

The self-adhesive articles obtained from the adhesive composition according to the invention can be produced according to the process as previously described for the self-adhesive articles according to the invention.

The self-adhesive article can be used in a bonding process comprising the steps of:

a) removing the non-stick protective film when present;

b) applying the article to a surface; and

c) applying pressure to the article.

According to one embodiment, wherein the self-adhesive article is a two-sided article, the method of bonding further comprises the step of applying the article bonded to the first surface to a second surface.

Examples

Different adhesive compositions were tested on two different types of support layers: PET carriers and carriers made from the foam according to the invention.

The following polymers were used:

GENIOSIL STP-15 (available from Wacker): polyethers of group P1 corresponding to formula (I) having two trimethoxy silane type end groups, with an average molar mass of about 10000g/mol, a polydispersity of about 1.6 and an amount of silyl functional groups of 0.200 meq/g of polymer;

GENIOSIL STP-30 (available from Wacker): polyethers of group P2 corresponding to formula (II) having two dimethoxysilane-type end groups, with an average molar mass of about 14493g/mol, a polydispersity of about 1.6 and an amount of silyl functional groups of 0.138 meq/g of polymer;

polyurethane a as described in international application WO 2009/106699: polyurethanes of group P1 corresponding to formula (I) having two trimethoxy silane type end groups, an average molar mass of about 16393g/mol, a dispersity of about 1.7 and an amount of silyl functional groups of 0.122 meq/g of polymer;

SPUR +. 1050MM (available from Momentive): polyurethanes of group P1 corresponding to formula (I) having two trimethoxy silane type end groups, an average molar mass of about 16393g/mol, a polydispersity of about 1.7 and an amount of silyl functional groups of 0.122 meq/g of polymer;

MS Polymer SAT 145 (commercially available from Kaneka): a polymer having one dimethoxysilane type end group, an average molar mass of about 3497g/mol, a dispersity of about 2.1 and an amount of silyl functional groups of 0.286 meq/g of polymer;

polymer Ex 8: polyethers of group P2 having two diethoxysilane-type end groups corresponding to formula (IIa), the average molar mass being about 5376g/mol and the amount of silyl functions being 0.372 meq/g;

polymer Ex 15: a polyether of group P3 corresponding to formula (IIIa) having 2 monoethoxysilane type end groups, the average molar mass being about 5263g/mol and the amount of silyl functions being 0.380 meq/g;

polymer Ex 6-18: polyethers of group P2 having 3 diethoxysilane-type end groups corresponding to formula (IIa), the average molar mass being about 7160g/mol and the amount of silyl functional groups being 0.419 meq/g;

polymer Ex 19: polyethers of group P1 having 3 trimethoxysilyl end groups corresponding to formula (Ia), with an average molar mass of about 6818g/mol and an amount of silyl functional groups of 0.440 meq/g;

polymer Ex 20: polyethers of group P1 having 2 trimethoxy silane type end groups corresponding to formula (Ia), with an average molar mass of about 5376g/mol and an amount of silyl functional groups of 0.372 meq/g;

polymer ExC 6: polyether of group P1 having 2 terminal groups of the trimethoxy silane type, the average molar mass being about 4000g/mol and the amount of silyl functions being 0.500 meq/g.

Polymer Ex8 was prepared according to the following procedure:

introducing 84.1g of polyol ACCLAIM 8200 (available from Bayer) under nitrogen and vacuum into a glass synthesis apparatus heated to about 85-90 ℃; followed by

Introducing 0.1g of catalyst BORCHI KAT VP 0244 (bismuth/zinc neodecanoate, available from Soci Tet Borchers, Inc.); followed by

-maintaining the apparatus under vacuum at 85-90 ℃ for about 1 hour; followed by

6.4g of isophorone diisocyanate are introduced;

-maintained at 85-90 ℃ under nitrogen for about 2 hours until an NCO functional group level of 1.5-1.9% is obtained (this level is measured by assaying the sample); followed by

-cooling the apparatus to 65-70 ℃; followed by

-9.01 g of GENIOSIL XL924 (N-cyclohexylaminomethyl-methyldiethoxysilane, commercially available from Wacker);

-maintaining at 70 ℃ under nitrogen atmosphere for about 1 hour until complete disappearance of the NCO functional groups.

Polymer Ex15 was prepared according to the following procedure:

-introducing 87.3g of polyol ACCLAIM 8200 (available from Bayer) under nitrogen atmosphere and under vacuum into a glass synthesis apparatus heated to about 85-90 ℃; followed by

6.6g of isophorone diisocyanate are introduced;

-cooling the apparatus to 65-70 ℃; followed by

6.14g of 3-aminopropyldimethyl-ethoxysilane are introduced; followed by

Polymer Ex19 was prepared according to the following procedure:

-introducing 82.18g of polyol ACCLAIM 6300 (available from Bayer) into a glass synthesis apparatus under nitrogen atmosphere and under vacuum, heated to about 85-95 ℃; followed by

Introducing 0.04g of catalyst BORCHI KAT VP 0244 (bismuth/zinc neodecanoate, available from Soci Tet Borchers, Inc.); followed by

Introducing 9.44g of isophorone diisocyanate;

-maintained at 85-90 ℃ under nitrogen for about 2 hours until an NCO functional group level of 1.8-2.2% is obtained (this level is measured by assaying the sample); followed by

-cooling the apparatus to 65-70 ℃; followed by

-introduction of 7.84g Silane A1110 (γ -aminopropyltrimethoxysilane, available from Momentive Corp.); followed by

-maintaining at 70 ℃ under nitrogen for about 1 hour until complete disappearance of the NCO functional groups.

Polymer Ex6-18 was prepared according to the following procedure:

-introducing 82.03g of polyol ACCLAIM 6300 (available from Bayer) into a glass synthesis apparatus under nitrogen atmosphere and under vacuum, heated to about 85-95 ℃; followed by

-introducing 9.45g of isophorone diisocyanate;

-cooling the apparatus to 65-70 ℃; followed by

-introduction of 7.98g of 3-aminopropylmethyl-diethoxysilane; followed by

Polymer Ex20 was prepared according to the following procedure:

introducing 84.71g of polyol ACCLAIM 8200 (available from Bayer) into a glass synthesis apparatus under nitrogen atmosphere and under vacuum, heating to about 85-90 ℃; followed by

-introducing 0.04g of catalyst BORCHI KAT ® VP 0244; followed by

6.5g of isophorone diisocyanate are introduced;

-maintained at 85-90 ℃ under nitrogen for about 2 hours until an NCO functional group level of 1.7-2.2% is obtained (this level is measured by assaying the sample); followed by

-cooling the apparatus to 65-70 ℃; followed by

Introduction of 8.23g N-ethyl-3-trimethoxysilyl-2-methylpropylamine; followed by

Polymer Ex C6 was prepared according to the following procedure:

80.3g of polyol ACCLAIM 8200 (available from Bayer) were introduced into a glass synthesis apparatus under nitrogen atmosphere and under vacuum, heated to about 85-90 ℃; followed by

-introducing 0.07g of catalyst BORCHI KAT ® VP 0244; followed by

Introduction of 8.1g of isophorone diisocyanate;

-cooling the apparatus to 65-70 ℃; followed by

-introduction of 11.2g N-ethyl-3-trimethoxysilyl-2-methylpropylamine; followed by

The following products were also used:

-DEROPHENE H150: terpene phenol type tackifying resins;

IRGANOX 1010 and IRGANOX 245: a stabilizer;

-K-KAT 5218: a crosslinking catalyst;

-vinylglycosyloxysilane (vinylglycosyloxysilane): an agent capable of absorbing water ("water scavenger").

Tables 1 and 1a show the components of the adhesive compositions tested. The amounts of the components are given in mass percent.

Adhesive compositions C1, C2, C3, C4, C5 and C6 correspond to comparative adhesive compositions.

Compositions 6, 8, 15, 18, 19 and 20 correspond to the adhesive compositions according to the invention.

Table 1: adhesive composition (% by mass)

Table 1 a: adhesive composition (mass%) (continue)

The properties of the self-adhesive article according to the invention (with a carrier layer in the form of a foam) were evaluated and compared with the properties of a comparative self-adhesive article (with a carrier layer made of PET).

The carrier layer in foam form used in these tests was foam TLSRZ 1200.8 available from Alveo having the following properties:

elongation at break in the length direction at 23 ℃, 408.3 ± 53%,

elongation at break in the width direction at 23 ℃, 390.3%,

bulk density, about 96.92kg/m³，

-a thickness, about 0.67mm,

young's modulus, 11.2. + -. 0.5 MPa.

The support layer made of PET used for the test had a thickness of 50 μm.

The compositions shown in Table 1 were mixed at about 50g/m²Is applied to both of the above-mentioned carrier layers to give a self-adhesive article.

Method for obtaining the self-adhesive articles tested: the various adhesive compositions were preheated to a temperature of about 100 ℃ and introduced into the barrel, from which the beads were extruded, and subsequently deposited close to the edges of the support layer, parallel to its width. The adhesive composition contained in the bead was then spread on an organosilicated support (non-stick protective film) using an applicator ("coater") with a lip-type nozzle moving from one side of the support layer to the opposite sideOr release liner) over the entire surface to provide a uniform layer of substantially constant thickness. Thus depositing a layer of composition corresponding to about 50g/m²Weight per unit area (thickness about 50 μm). The support layer thus coated with the adhesive composition was subsequently placed in an oven supplied with steam at a temperature of about 120 ℃ so that the amount of water was about 50g/m³And the distribution is uniform. The residence time in the oven was about 5 minutes, and the adhesive composition was allowed to crosslink to give an adhesive layer. Finally, once removed from the oven, the crosslinked adhesive layer was laminated to the desired carrier layer (foam Alveo TLSRZ 1200.8 or PET 50 μm carrier).

Static shear time of the glued joint:

the adhesion of the support layer coated with the crosslinking composition, which is maintained at high temperature, is evaluated within the latest 5 hours after production by a test which determines the static shear time of the adhesive bond seam on PET at 90 ℃ and on foam at 70 ℃. For this test, reference is made to method 8 of FINAT. The principle is as follows.

Samples in the form of rectangular strips (25mm x 75mm) were cut from a PET carrier layer or a foam carrier layer coated with the previously prepared cross-linking composition within up to 5 hours after preparation. After complete removal of the release liner, a square portion with 25mm sides at the end of the adhesive strip was secured to the glass plate.

The test panels thus obtained are introduced in a substantially vertical position, using a suitable support (support), into an oven which is at 90 ℃ for the samples made of PET; whereas for the samples made with foam the oven was at 70 ℃ and the unglued part with a length of 50mm was located under the plate. After thermal equilibration, the portion of the strip remaining free was attached to a 1kg weight, the entire device remaining in the oven at 90 ℃ and 70 ℃ for the PET and foam carriers, respectively, for the entire duration of the test.

The adhesive seam providing the attachment of the strip to the panel is subjected to shear stress under the action of the weight. To better control this stress, the test panel was actually placed at an angle of 2 ° to the vertical.

The last time the strip detached from the plate after the glued seam broke under the effect of this stress was recorded.

This time is shown in tables 2 and 2 a.

Table 2: properties of the self-adhesive article

Table 2 a: properties of the self-adhesive article

Comparative examples C1, C2, C3, C4, C5 and C6 show that self-adhesive articles comprising the same adhesive composition have different properties depending on the carrier layer used. In fact, these examples give good results with respect to shear strength (resistance greater than 24h) with PET carriers, whereas these comparative examples do not give satisfactory shear strength (resistance comprised between 0.1 hour, 0.2 hour, 1 hour or 5 hours) with carriers in the form of foam.

These tests show that none of the existing adhesive compositions having satisfactory properties on PET carriers have satisfactory properties on a conformable carrier such as the foam type claimed.

In contrast, example 8 according to the invention gives good results with a support in the form of a foam, wherein the adhesive composition comprises a single polymer corresponding to formula (IIa).

Similarly, example 18 gives good results with a support in the form of a foam, wherein the adhesive composition comprises a polymer of formula (IIa) and a polymer of formula (II).

Example 20 contains a polymer of formula (Ia) with silyl functional groups in an amount of 0.372meq/g within the claimed range and shows good results with a support in foam form.

In contrast, comparative example C6 contained a polymer of formula (Ia) with silyl functional groups in an amount of 0.500meq/g, which is outside the claimed range. This example C6 does not give satisfactory shear strength in the case of a carrier in the form of a foam.

Examples 15 and 19 give satisfactory results with respect to shear strength, wherein the composition comprises a mixture of two polymers belonging to two different groups from P1, P2, P3 and P4.

Of course, the invention is not limited to the examples and embodiments described and illustrated, but is capable of many variations as will be appreciated by those skilled in the art.

Claims

1. Self-adhesive article comprising a carrier layer coated with an adhesive layer, said carrier layer having an elongation at break of 50-1200% and 25-1200kg/m³The adhesive layer is obtained by crosslinking an adhesive composition comprising:

a) a mixture of at least two polymers selected from polyurethanes and polyethers having one, two or three mono-, di-or tri-alkoxysilane-type end groups, said mixture comprising at least one polymer corresponding to one of the formulae (Ia), (IIa), (IIIa) and (IVa) and at least one polymer corresponding to one of the formulae (I), (II), (III) or (IV),

wherein:

when a polymer having two or three monoalkoxysilane-type end groups is present, the mixture comprises up to 15% by weight of the polymer, relative to the total weight of the mixture,

b) at least one tackifying resin, and

c) at least one crosslinking catalyst;

wherein:

the polymer of formula (IVa) is a polyurethane or polyether comprising one hydrolysable end group of the mono-, di-and/or tri-alkoxysilane type and corresponding to the formula, wherein the amount of silyl functions is less than or equal to 0.480meq/g of polymer:

and wherein:

in the above-mentioned formulae (Ia), (IIa), (IIIa) and (IVa) and in the above-mentioned formulae (I), (II), (III) and (IV),

b represents one of the following two formulae:

wherein D and T represent a linear, branched or cyclic hydrocarbon radical comprising from 2 to 66 carbon atoms, which is saturated or unsaturated, optionally comprising one or more heteroatoms,

-R¹denotes a divalent hydrocarbon radical comprising from 5 to 15 carbon atoms, which is aromatic or aliphatic, straight-chain, branched or cyclic,

-R⁶denotes a linear, branched or cyclic hydrocarbon radical comprising from 1 to 22 carbon atoms, which is saturated or unsaturated, optionally comprising one or more heteroatoms,

-p is an integer equal to 0, 1 or 2,

-f is an integer equal to 2 or 3.

2. The self-adhesive article according to claim 1, wherein the carrier layer has a young's modulus of less than or equal to 300 MPa.

3. The self-adhesive article according to claim 1, wherein the carrier layer is in the form of a foam.

4. The self-adhesive article according to claim 1, wherein the carrier layer is in the form of one or more polymer layers.

5. The self-adhesive article according to claim 1, wherein the adhesive composition comprises:

-20-85% by weight, relative to the total weight of the adhesive composition, of a mixture of polymers as defined in claim 1,

-0.01 to 3 wt.%, relative to the total weight of the adhesive composition, of at least one crosslinking catalyst,

with the proviso that the total amount of the mixture of polymers, the tackifying resin and the crosslinking catalyst does not exceed 100 wt.%, relative to the total weight of the adhesive composition.

6. The self-adhesive article according to claim 1, wherein the tackifying resin has a number average molar mass of between 100Da and 5kDa and is selected from:

(ii) a resin obtainable by polymerization of α -methylstyrene,

(iii) rosin of natural or modified origin,

(iv) resins obtained by hydrogenation, polymerization or copolymerization of a mixture of unsaturated aliphatic hydrocarbons having 5, 9 or 10 carbon atoms derived from petroleum fractions,

(vi) copolymers based on natural terpenes, and

(vii) an acrylic resin.

7. A mixture of polymers suitable for use in the adhesive composition as defined in claim 1, said mixture comprising at least two polymers belonging to two different groups selected from the group consisting of P1, P2, P3 and P4, said mixture comprising at least one polymer corresponding to one of the formulae (Ia), (IIa), (IIIa) and (IVa) and wherein the amount of silyl functional groups is less than or equal to 0.480meq/g of polymer,

wherein:

-when a polymer of group P4 is present, the mixture comprises at most 15% by weight, relative to the total weight of the mixture of polymers, of at least one polyurethane or at least one polyether of group P4;

8. A mixture of polymers according to claim 7, comprising:

-at least one polymer corresponding to formula (IIa).

9. A mixture of polymers according to claim 7, comprising:

-at least one polymer corresponding to formula (IIa).

10. A mixture of polymers according to claim 7, comprising:

-at least one polymer corresponding to one of the formulae (Ia), (IIa), (IIIa) or (IVa), and

-at least one polymer corresponding to one of the formulae (I), (II), (III) or (IV),

wherein:

-when a polymer of formula (IIIa) and/or (III) is present, the mixture comprises at most 15% by weight of polymer of formula (IIIa) and/or (III) relative to the total weight of the mixture of polymers,

-when a polymer of formula (IVa) and/or (IV) is present, the mixture comprises at most 15% by weight of polymer of formula (IVa) and/or (IV), relative to the total weight of the mixture of polymers;

in the above formulae (I), (II), (III) and (IV):

b represents one of the following two formulae:

-R⁶denotes a straight, branched or cyclic chain containing 1 to 22 carbon atomsA cyclic hydrocarbon group, which is saturated or unsaturated, optionally containing one or more heteroatoms,

n is such that formula- [ OR ]²]_nThe polyether blocks of (A) have an average molar mass of from 300g/mol to 40,000g/mol,

-p is an integer equal to 0, 1 or 2,

-f is an integer equal to 2 or 3.

11. An adhesive composition suitable for use in the production of self-adhesive articles comprising:

-a mixture of polymers according to claim 7,

-at least one tackifying resin, and

-at least one crosslinking catalyst.

12. An adhesive composition according to claim 11, comprising:

-20-85% by weight of the mixture of polymers, relative to the total weight of the adhesive composition,